Audiovisual signal routing and distribution system

Abstract

An audiovisual signal is converted from a native format to a digital, packetized interchange format and transported between a capture node and a display node through a switch. The display node converts the audiovisual signal from the interchange format to a displayable format and causes display of the audiovisual signal. The use of a switch for video routing and distribution allows one-to-one, one-to-many, many-to-one, and many-to-many distribution. The use of a device-independent interchange format allows concurrent distribution of multiple heterogeneous audiovisual signals.

What is claimed is: 
     
       1. A video distribution system, the video distribution system comprising:
 a capture node comprising:
 capture logic for receiving a non-packetized video signal in a scanline-based native format; 
 first signal format conversion logic, which is operatively coupled to the capture logic, for converting the video signal from the native format to a scanline-based interchange format by packetizing the video signal; 
 first communication logic, which is operatively coupled to the first signal format conversion logic, for communicating with a display node and transporting the video signal in the interchange format; and 
 negotiation logic, operatively coupled to the first signal format conversion logic; 
 
 the display node comprising:
 second signal format conversion logic, which is operatively coupled to the first communication logic, for converting the video signal from the interchange format to a scanline-based displayable format; 
 display driving logic, operatively coupled to the second signal format conversion logic, for sending the video signal in the displayable format to a display device such that the display device displays the video signal in the displayable format; and 
 negotiation logic, operatively coupled to the second signal format conversion logic; 
 
 
       wherein the negotiated logic of the capture node and the negotiation logic of the display node cooperatively select the interchange format. 
     
     
       2. The video distribution system of  claim 1  wherein the capture node further comprises negotiation logic, operatively coupled to the first signal format conversion logic;
 further wherein the display node further comprises negotiation logic operatively coupled to the second signal format conversion logic; 
 further wherein the negotiation logic of the capture node and the negotiation logic of the display node cooperatively select the interchange format according to video processing capabilities of the capture node. 
 
     
     
       3. The video distribution system of  claim 1  wherein the capture node further comprises negotiation logic, operatively coupled to the first signal format conversion logic;
 further wherein the display node further comprises negotiation logic operatively coupled to the second signal format conversion logic; 
 further wherein the negotiation logic of the capture node and the negotiation logic of the display node cooperatively select the interchange format according to video processing capabilities of the display node. 
 
     
     
       4. The video distribution system of  claim 1  wherein the capture node further comprises negotiation logic, operatively coupled to the first signal format conversion logic;
 further wherein the display node further comprises negotiation logic operatively coupled to the second signal format conversion logic; 
 further wherein the negotiation logic of the capture node and the negotiation logic of the display node cooperatively select the interchange format according to video processing capabilities of the display device. 
 
     
     
       5. The video distribution system of  claim 1  wherein receiving comprises:
 receiving the video signal from an external video source. 
 
     
     
       6. The video distribution system of  claim 1  wherein transporting comprises sending the video signal in the interchange format through a packet switch. 
     
     
       7. The video distribution system of  claim 6  wherein sending comprises sending the video signal in the interchange format through two or more packet switches in parallel. 
     
     
       8. The video distribution system of  claim 1  wherein the interchange format is a digital representation of scanlines in the native format. 
     
     
       9. The video distribution system of  claim 1  wherein the interchange format includes digital packets capable of transport through a packet switch. 
     
     
       10. The video distribution system of  claim 1  wherein the native format is different from the displayable format. 
     
     
       11. The video distribution system of  claim 1  wherein converting the video signal from the native format to the interchange format comprises:
 dropping one or more frames of the video signal so as to result in a frame rate of the video signal in the interchange format that is less than a frame rate of the video signal in the native format. 
 
     
     
       12. The video distribution system of  claim 1  wherein converting the video signal from the native format to the interchange format comprises:
 downscaling frames of the video signal so as to result in a frame size of the video signal in the interchange format that is less than a frame size of the video signal in the native format. 
 
     
     
       13. The video distribution system of  claim 1  wherein converting the video signal from the native format to the interchange format comprises:
 changing color space representation of pixels of the video signal. 
 
     
     
       14. The video distribution system of  claim 1  wherein converting the video signal from the native format to the interchange format comprises:
 interlacing frames of the video signal. 
 
     
     
       15. The video distribution system of  claim 1  wherein converting the video signal from the native format to the interchange format comprises:
 de-interlacing frames of the video signal. 
 
     
     
       16. The video distribution system of  claim 1  wherein converting the video signal from the interchange format to the displayable format comprises:
 adding one or more frames to the video signal so as to result in a frame rate of the video signal in the displayable format that is greater than a frame rate of the video signal in the interchange format. 
 
     
     
       17. The video distribution system of  claim 1  wherein converting the video signal from the interchange format to the displayable format comprises:
 upscaling frames of the video signal so as to result in a frame size of the video signal in the displayable format that is greater than a frame size of the video signal in the interchange format. 
 
     
     
       18. The video distribution system of  claim 1  wherein converting the video signal from the interchange format to the displayable format comprises:
 changing color space representation of pixels of the video signal. 
 
     
     
       19. The video distribution system of  claim 1  wherein converting the video signal from the interchange format to the displayable format comprises:
 interlacing frames of the video signal. 
 
     
     
       20. The video distribution system of  claim 1  wherein converting the video signal from the interchange format to the displayable format comprises:
 de-interlacing frames of the video signal. 
 
     
     
       21. The video distribution system of  claim 1  wherein the receiving by the capture logic, the converting of the video signal from the native format to the interchange format by the first signal format conversion logic, the transporting by the communications logic, the converting of the video signal from the interchange format to the displayable format by the second signal format conversion logic, and the sending by the display driving logic are performed concurrently with one another. 
     
     
       22. The video distribution system of  claim 21  wherein the receiving by the capture logic, the converting of the video signal from the native format to the interchange format by the first signal format conversion logic, the transporting by the communications logic, the converting of the video signal from the interchange format to the displayable format by the second signal format conversion logic, and the sending by the display driving logic are performed in real time. 
     
     
       23. The video distribution system of  claim 1  further comprising negotiation logic, which is operatively coupled to the logic, that (i) receives data representing a plurality of predetermined interchange formats implemented by a remote one of the capture node and the display node; (ii) determines that one or more supported ones of the predetermined interchange formats are implemented a local one of the capture node and the display node; and (iii) selects one of the supported predetermined interchange formats as the interchange format. 
     
     
       24. The video distribution system of  claim 23  wherein selecting comprises:
 considering an amount of loss of fidelity of at least one of the supported predetermined interchange formats relative to the native format; 
 considering an amount of excess signal of at least one of the supported predetermined interchange formats relative to the displayable format; and 
 considering an amount of signal bandwidth to or from remote node of one of the capture node and display node. 
 
     
     
       25. The video distribution system of  claim 1  further comprising:
 negotiation logic, operatively coupled to the first signal format conversion logic, for selecting the interchange format according to an amount of available bandwidth to the display node. 
 
     
     
       26. The video distribution system of  claim 25  wherein selecting comprises:
 determining a requisite bandwidth for the video signal in the interchange format; and 
 comparing the requisite bandwidth to the amount of available bandwidth. 
 
     
     
       27. The video distribution system of  claim 26  wherein the negotiation logic also determines that the requisite bandwidth exceeds the amount of available bandwidth. 
     
     
       28. The video distribution system of  claim 27  wherein the negotiation logic also adapts the interchange format to reduce bandwidth required by the video signal in the interchange format. 
     
     
       29. The video distribution system of  claim 28  wherein the negotiation logic adapts the interchange format by at least:
 configuring the interchange format to include a frame rate that is less than a frame rate of the native format such that converting comprises dropping one or more frames of the video signal. 
 
     
     
       30. The video distribution system of  claim 28  wherein the negotiation logic adapts the interchange format by at least:
 configuring the interchange format to include a color depth that is less than a color depth of the native format such that converting comprises reducing a color depth of the video signal. 
 
     
     
       31. The video distribution system of  claim 28  wherein the negotiation logic adapts the interchange format by at least:
 configuring the interchange format to include a color space that is different from a color space of the native format. 
 
     
     
       32. The video distribution system of  claim 28  wherein the negotiation logic adapts the interchange format by at least:
 configuring the interchange format to include a frame size that is less than a frame size of the native format such that converting comprises downscaling frames of the video signal. 
 
     
     
       33. The video distribution system of  claim 28  wherein the first signal format conversion logic applies lossless compression techniques to the video signal. 
     
     
       34. The video distribution system of  claim 28  wherein the first signal format conversion logic applies lossy compression techniques to the video signal. 
     
     
       35. The video distribution system of  claim 1  wherein sending comprises:
 determining a maximum data quantity; 
 determining a minimum time interval; and 
 sending no more than the maximum data quantity of the video signal during a time interval which is no shorter than the minimum time interval. 
 
     
     
       36. The video distribution system of  claim 35  wherein the maximum data quantity is determined according to a minimum-sized buffer through which the video signal travels to the display node. 
     
     
       37. The video distribution system of  claim 35  wherein the maximum data quantity is determined according to other traffic traveling through at least one buffer through which the video signal travels to the display node. 
     
     
       38. The video distribution system of  claim 35  wherein the maximum data quantity and the minimum time interval are determined according to an amount of available bandwidth from the capture node to the display node. 
     
     
       39. The video distribution system of  claim 1  further comprising:
 a second display node comprising: 
 third signal format conversion logic, which is operatively coupled to the communications logic, for converting the video signal from the interchange format to a second scanline-based displayable format; and 
 second display driving logic, operatively coupled to the third signal format conversion logic, for sending the video signal in the second displayable format to a second display device such that the second display device displays the video signal in the second displayable format. 
 
     
     
       40. The video distribution system of  claim 1  wherein the first signal format conversion logic converts the video signal from the native format to a second scanline-based interchange format; and
 further wherein the communications logic transports the video signal in the second interchange format to a second remotely located display node such that the second display node converts the video signal from the second interchange format to a second scanline-based displayable format and causes display of the video signal in the second displayable format. 
 
     
     
       41. The video distribution system of  claim 1  wherein converting comprises converting the video signal from the native format to two or more scanline-based interchange formats; and
 further wherein transporting comprises, for each of the two or more interchange formats, transporting the video signal in said each of the two or more interchange formats to one or more display nodes such that each of the one or more display nodes converts the video signal from said each of the two or more interchange formats to a respective scanline-based displayable format and causes display of the video signal in the respective displayable format. 
 
     
     
       42. The video distribution system of  claim 1  further comprising:
 a second capture node comprising: 
 second capture logic for receiving a second video signal in a second scanline-based native format; and 
 third signal format conversion logic, which is operatively coupled to the second capture logic and the communications logic, for converting the second video signal from the second native format to a second scanline-based interchange format; 
 wherein the communications logic transports the second video signal in the second interchange format from the second capture node to the display node while concurrently transporting the video signal in the first-mentioned interchange format from the capture node to the display node; 
 further wherein the second signal format conversion logic converts the second video signal from the second interchange format to the displayable format; and causes display of the second video signal in the displayable format. 
 
     
     
       43. The video distribution system of  claim 42  wherein the display node further comprises user interface logic, operatively coupled to the communications logic, for providing a user interface for selecting the video signal and the second video signal from one or more available video signals. 
     
     
       44. The video distribution system of  claim 42  wherein the display driving logic causes display of the video signal and the second video signal by at least:
 compositing the video signal and the second video signal into composite video display. 
 
     
     
       45. The video distribution system of  claim 44  wherein the composite video display combines the video signal and the second video signal in a picture-in-picture arrangement. 
     
     
       46. The video distribution system of  claim 44  wherein the composite video display combines the video signal and the second video signal in a picture-beside-picture arrangement. 
     
     
       47. The video distribution system of  claim 44  wherein the composite video display combines the video signal and the second video signal in a picture-over-picture arrangement. 
     
     
       48. The video distribution system of  claim 1  wherein the interchange format includes timestamps associated with the video signal. 
     
     
       49. The video distribution system of  claim 48  wherein the first signal format conversion logic inserts timestamps in an audio signal associated with the video signal wherein the timestamps that are inserted in the audio signal are related to the timestamps of the video signal. 
     
     
       50. The video distribution system of  claim 49  wherein the display driving logic synchronizes playback of the video signal and the audio signal in accordance with the timestamps of both the video signal and the audio signals. 
     
     
       51. The video distribution system of  claim 1  wherein the display node further comprises:
 user interface logic, operatively coupled to the communications logic, for providing a user interface for selecting the video signal from one or more available video signals. 
 
     
     
       52. The video distribution system of  claim 1  wherein transporting comprises:
 transporting the video signal in the interchange format through at least two separate communications channels to the display node. 
 
     
     
       53. A video distribution system for displaying a video signal, the video distribution system comprising:
 a capture node comprising:
 capture logic for receiving a non-packetized video signal in a scanline-based native format; 
 first signal format conversion logic, which is operatively coupled to the capture logic, for converting the video signal from the native format to a first scanline-based interchange format by packetizing the video signal; 
 first communication logic, which is operatively coupled to the first signal format conversion logic, for transporting the video signal in the first interchange format; and 
 negotiation logic, operatively coupled to the first signal format conversion logic 
 
 an intermediate node comprising:
 second signal format conversion logic, which is operatively coupled to the first communication logic, for converting the video signal from the first interchange format to a second scanline-based interchange format; and 
 
 a display node comprising:
 second communication logic, which is operatively coupled to the second signal format conversion logic, for receiving the video signal in the second interchange format; 
 third signal format conversion logic, which is operatively coupled to the second communications logic, for converting the video signal from the second interchange format to a scanline-based displayable format; 
 display driving logic, operatively coupled to the third signal format conversion logic, for sending the video signal in the displayable format to a display device such that the display device displays the video signal in the displayable format; 
 negotiation logic, operatively coupled to the third signal format conversion logic; and 
 
 wherein the negotiated logic of the capture node and the negotiation logic of the display node cooperatively select the interchange format. 
 
     
     
       54. A method for displaying a video signal, the method comprising:
 receiving a non-packetized video signal in a scanline-based native format into a capture node; 
 selecting cooperatively a scanline-based interchange format between the capture node and a display node; 
 converting the video signal from the native format to the scanline-based interchange format by packetizing the video signal; 
 transporting the video signal in the interchange format from the capture node to the display node; 
 converting the video signal from the interchange format to a scanline-based displayable format; and 
 sending the video signal in the displayable format to a display device that displays the video signal. 
 
     
     
       55. The method of  claim 54  further comprising:
 selecting the interchange format according to video processing capabilities of the capture node. 
 
     
     
       56. The method of  claim 54  further comprising:
 selecting the interchange format according to video processing capabilities of the display node. 
 
     
     
       57. The method of  claim 54  further comprising:
 selecting the interchange format according to video processing capabilities of the display device. 
 
     
     
       58. The method of  claim 54  wherein receiving comprises:
 receiving the video signal from an external video source. 
 
     
     
       59. The method of  claim 54  wherein transporting comprises sending the video signal in the interchange format through a packet switch. 
     
     
       60. The method of  claim 59  wherein sending comprises sending the video signal in the interchange format through two or more packet switches in parallel. 
     
     
       61. The method of  claim 54  wherein the interchange format is a digital representation of scanlines in the native format. 
     
     
       62. The method of  claim 54  wherein the interchange format includes digital packets capable of transport through a packet switch. 
     
     
       63. The method of  claim 54  wherein the native format is different from the displayable format. 
     
     
       64. The method of  claim 54  wherein converting the video signal from the native format to the interchange format comprises:
 dropping one or more frames of the video signal so as to result in a frame rate of the video signal in the interchange format that is less than a frame rate of the video signal in the native format. 
 
     
     
       65. The method of  claim 54  wherein converting the video signal from the native format to the interchange format comprises:
 downscaling frames of the video signal so as to result in a frame size of the video signal in the interchange format that is less than a frame size of the video signal in the native format. 
 
     
     
       66. The method of  claim 54  wherein converting the video signal from the native format to the interchange format comprises:
 changing color space representation of pixels of the video signal. 
 
     
     
       67. The method of  claim 54  wherein converting the video signal from the native format to the interchange format comprises:
 interlacing frames of the video signal. 
 
     
     
       68. The method of  claim 54  wherein converting the video signal from the native format to the interchange format comprises:
 de-interlacing frames of the video signal. 
 
     
     
       69. The method of  claim 54  wherein converting the video signal from the interchange format to the displayable format comprises:
 adding one or more frames to the video signal so as to result in a frame rate of the video signal in the displayable format that is greater than a frame rate of the video signal in the interchange format. 
 
     
     
       70. The method of  claim 54  wherein converting the video signal from the interchange format to the displayable format comprises:
 upscaling frames of the video signal so as to result in a frame size of the video signal in the displayable format that is greater than a frame size of the video signal in the interchange format. 
 
     
     
       71. The method of  claim 54  wherein converting the video signal from the interchange format to the displayable format comprises:
 changing color space representation of pixels of the video signal. 
 
     
     
       72. The method of  claim 54  wherein converting the video signal from the interchange format to the displayable format comprises:
 interlacing frames of the video signal. 
 
     
     
       73. The method of  claim 54  wherein converting the video signal from the interchange format to the displayable format comprises:
 de-interlacing frames of the video signal. 
 
     
     
       74. The method of  claim 54  wherein the receiving, the converting of the video signal from the native format to the interchange format, the transporting, the converting of the video signal from the interchange format to the displayable format, and the displaying are performed concurrently with one another. 
     
     
       75. The method of  claim 74  wherein the receiving, the converting of the video signal from the native format to the interchange format, the transporting, the converting of the video signal from the interchange format to the displayable format, and the displaying are performed in real time. 
     
     
       76. The method of  claim 54  further comprising:
 receiving data representing a plurality of predetermined scanline-based interchange formats implemented by a remote one of the capture and display nodes; 
 determining that one or more supported ones of the predetermined interchange formats are implemented a local one of the capture node and the display node; and 
 selecting one of the supported predetermined interchange formats as the interchange format. 
 
     
     
       77. The method of  claim 76  wherein selecting comprises:
 considering an amount of loss of fidelity of at least one of the supported predetermined interchange formats relative to the native format; 
 considering an amount of excess signal of at least one of the predetermined supported interchange formats relative to the displayable format; and 
 considering an amount of signal bandwidth to or from the remote node of the capture and display nodes. 
 
     
     
       78. The method of  claim 54  further comprising:
 selecting the interchange format according to an amount of available bandwidth to the display node. 
 
     
     
       79. The method of  claim 78  wherein selecting comprises:
 determining a requisite bandwidth for the video signal in the interchange format; and 
 comparing the requisite bandwidth to the amount of available bandwidth. 
 
     
     
       80. The method of  claim 79  further comprising:
 determining that the requisite bandwidth exceeds the amount of available bandwidth. 
 
     
     
       81. The method of  claim 80  further comprising:
 adapting the interchange format to reduce bandwidth required by the video signal in the interchange format. 
 
     
     
       82. The method of  claim 81  wherein adapting comprises:
 configuring the interchange format to include a frame rate that is less than a frame rate of the native format such that converting comprises dropping one or more frames of the video signal. 
 
     
     
       83. The method of  claim 81  wherein adapting comprises:
 configuring the interchange format to include a color depth that is less than a color depth of the native format such that converting comprises reducing a color depth of the video signal. 
 
     
     
       84. The method of  claim 81  wherein adapting comprises:
 configuring the interchange format to include a color space that is different from a color space of the native format. 
 
     
     
       85. The method of  claim 81  wherein adapting comprises:
 configuring the interchange format to include a frame size that is less than a frame size of the native format such that converting comprises downscaling frames of the video signal. 
 
     
     
       86. The method of  claim 81  wherein converting comprises:
 applying lossless compression techniques to the video signal. 
 
     
     
       87. The method of  claim 81  wherein converting comprises:
 applying lossy compression techniques to the video signal. 
 
     
     
       88. The method of  claim 54  wherein sending comprises:
 determining a maximum data quantity; 
 determining a minimum time interval; and 
 sending no more than the maximum data quantity of the video signal during a time interval which is no shorter than the minimum time interval. 
 
     
     
       89. The method of  claim 88  wherein the maximum data quantity is determined according to a minimum-sized buffer through which the video signal travels to the display node. 
     
     
       90. The method of  claim 88  wherein the maximum data quantity is determined according to other traffic traveling through at least one buffer through which the video signal travels to the display node. 
     
     
       91. The method of  claim 88  wherein the maximum data quantity and the minimum time interval are determined according to an amount of available bandwidth from the capture node to the display node. 
     
     
       92. The method of  claim 54  further comprising:
 sending the video signal in the interchange format to a second remotely located display node such that the second remotely located display node converts the video signal from the interchange format to a second scanline-based displayable format and causes display of the video signal in the second displayed format. 
 
     
     
       93. The method of  claim 54  further comprising:
 converting the video signal from the native format to a scanline-based second interchange format; and 
 sending the video signal in the second interchange format to a second remotely located display node such that the second display node converts the video signal from the second interchange format to a second scanline-based displayable format and causes display of the video signal in the second displayable format. 
 
     
     
       94. The method of  claim 54  wherein converting comprises converting the video signal from the native format to two or more interchange formats; and
 further wherein sending comprises, for each of the two or more interchange formats, sending the video signal in each of the two or more scanline-based interchange formats to one or more display nodes such that each of the one or more display nodes converts the video signal from the interchange format to a respective scanline-based displayable format and causes display of the video signal in the respective displayable format. 
 
     
     
       95. The method of  claim 54  further comprising:
 concurrently with the receiving of the video signal in the first-mentioned interchange format, receiving a second video signal in a second scanline-based interchange format to which the second video signal has been converted from a second scanline-based native format by a second remotely located capture node; 
 converting the second video signal from the second interchange format to the displayable format; and 
 displaying the second video signal in the displayable format. 
 
     
     
       96. The method of  claim 95  further comprising:
 providing a user interface for selecting the video signal and the second video signal from one or more available video signals. 
 
     
     
       97. The method of  claim 95  wherein displaying the video signal and displaying the second video signal comprises:
 compositing the video signal and the second video signal into composite video display. 
 
     
     
       98. The method of  claim 97  wherein the composite video display combines the video signal and the second video signal in a picture-in-picture arrangement. 
     
     
       99. The method of  claim 97  wherein the composite video display combines the video signal and the second video signal in a picture-beside-picture arrangement. 
     
     
       100. The method of  claim 97  wherein the composite video display combines the video signal and the second video signal in a picture-over-picture arrangement. 
     
     
       101. The method of  claim 54  wherein the interchange format includes timestamps associated with the video signal. 
     
     
       102. The method of  claim 101  further comprising inserting timestamps in an audio signal associated with the video signal wherein the timestamps that are inserted in the audio signal are related to the timestamps of the video signal. 
     
     
       103. The method of  claim 102  wherein displaying comprises:
 synchronizing playback of the video signal and the audio signal in accordance with the timestamps of both the video signal and the audio signal. 
 
     
     
       104. The method of  claim 54  further comprising:
 providing a user interface for selecting the video signal from one or more available video signals. 
 
     
     
       105. The method of  claim 54  wherein transporting comprises:
 transporting the video signal in the interchange format through at least two separate communications channels to the display node. 
 
     
     
       106. A method for displaying a video signal, the method comprising:
 receiving a non-packetized video signal in a scanline-based native format into a capture node; 
 converting the video signal from the native format to a first scanline-based interchange format by packetizing the video signal; 
 transporting the video signal in the first interchange format from the capture node to an intermediate signal processing node; 
 converting the video signal from the first interchange format to a second scanline-based interchange format; 
 transporting the video signal in the second interchange format from the intermediate signal processing node to a display node; 
 converting the video signal from the second interchange format to a scanline-based displayable format; and 
 sending the video signal in the displayable format to a display device such that the display device displays the video signal in the displayable format; 
 wherein further said interchange format is cooperatively selected by said capture node and said display node.